This invention relates to laboratory and production work stations such as for assembly, testing and operation of sensitive electronic devices, and more particularly to a chair for safely discharging static electricity.
It is well known that certain electronic devices can easily be damaged by discharges of static electricity. To prevent such damage and to avoid worker discomfort associated therewith, electrically conductive grounded chairs have been used to provide a discharge path for static electricity that does not damage the electronic devices.
A further development of the prior art is the use of electrically conductive cushions or cushion coverings to provide a conductive chair that is comfortable to sit in.
A disadvantage of the electrically conductive chairs of the prior art is that an occupant seated in such a chair can be electrically shocked, and possibly injured by contact with points of relatively low voltage commonly present in the working environment. Where no conductive chair or other path to ground is used, a worker can safely touch conductors having a single elevated potential in access of 100 volts without shock or injury.
Another disadvantage of chairs having electrically conductive cushions or cushion coverings in the prior art is that the electrically conductive materials are expensive to produce.
Accordingly, there is a need for a chair that safely discharges static electricity, without subjecting an occupant to shock if he touches a conductor having moderately elevated potential, and is economical to produce.